Very nice. As a novice to all this, but starting to image larger narrow band targets... have not done well with this tiny object. How come you are using 5' subs and not all longer? I see you also have some 29' ones. Theory?

That's great Bill! A lot of NII in there. How did you map the colors/blend in the narrowband data?

Derek

for this one i just did a simple "balanced NOO" (NII = red, OIII = green and blue) for the star field (nebula was all teal). used a slight stretch to lighten the background stars, to match the red stars brought out below.

did a separate narrow band balance pass to bring out the red fliers. don't remember the multiple, but i think it was 4-8x to the NII red channel. this of course turned all the stars red except the saturated central star, hence the first step above. this was a purist linear stretch as i was concentrating on the bright core. followed by a few rounds of RL deconvolution.

Very nice. As a novice to all this, but starting to image larger narrow band targets... have not done well with this tiny object. How come you are using 5' subs and not all longer? I see you also have some 29' ones. Theory?

sorry for the typo, longer subs were 20 minutes.

several reasons for short subs:
1. the NII signal is very weak (see response to derek above)
so in order to pick it up i had to go with much longer exposures, and stretch the red data more in order to bring out the red in the color picture (this is a hallmark of narrow band processing). conversely the central OIII signal is quite strong (this is a bright PN!)

since the NII data was relatively weak, due to inherently low signal, not much point to going deeper with OIII as my intent was to portray the two color channels together.

this nebula does have a faint outer OIII shell, so it's not crazy to go with longer exposures too. one of the difficulties with small bright planetaries like this is that this will generate massive diffraction spikes if you have a scope with a spider (reason i don't). and can make for blooms. even my NABG chip will give artifacts (not quite blooms) if you really saturate it. can be processed out in part, but it's a pain.